PCR (polymerase chain reaction) is a technology that a specific region of template DNA is repeatedly heated and cooled, the specific region is successively replicated, and the DNA having the specific region is amplified exponentially. The PCR is widely used for the purposes of analysis and diagnosis in various fields like biotechnology, genetic engineering, medicine and so on. Recently, a variety of devices for efficiently conducting the PCR have been developed.
According to a conventional PCR device, a container in which a sample solution having template DNA is accommodated is mounted on a single heater, and the container is repeatedly heated and cooled, thus conducting PCR. Since the PCR device has one heater, in this case, it is not complicated in structure, but it has to have a complicated circuit for controlling accurate temperatures. Further, the heating and the cooling need to be repeatedly carried out with one single heater which resulting in unpreferably extending the total time consumed for the PCR.
According to another conventional PCR device, further, a plurality of heaters having PCR temperatures are mounted, and a sample solution having template DNA flows along one channel passing through the heaters, thus conducting PCR. Since the PCR device has the plurality of heaters, the PCR device has a relatively simple circuit, but has to have a long channel passing through high temperature heaters and lower temperature heaters. Thus, the PCR device has complicated structure. Further, an additional controller is required to control the flow rate of the sample solution which includes the DNA and flows along the channel passing through the heaters.
On the other hand, recently, there have been proposed PCR devices capable of increasing PCR yield, recognizing PCR process in real time, and further achieving miniaturization and portability through miniaturized heaters. Since the performance of the miniaturized heaters gives a big influence on the PCR yield, in this case, it is very important to accurately control given temperatures of the miniaturized heaters. Accordingly, there is a definite need to develop a new PCR device capable of drastically reducing PCR time, providing reliable PCR yield, and achieving miniaturization and portability thereof.